Let's go to lara, live, all morning long, at buckingham palace, with new details on the royal baby. Good morning, lara. Good morning, george. What a joy to be here on this day of celebration here in england. Folks cheering and giving a thumbs-up as they pass. Buckingham palace behind me. And the papers shouting out the great news. There's the picture on "the times." We're expecting. And I love this one. Kate expectations. But theris also a sense of concern for kate and the royal heir. Just moments ago, prince william arrived back at the hospital to visit his pregnant wife, kate. The newly announced mother-to-be is being treated for a condition called hyperemetis gravidarum. The duchess needed to be hospitalized. William and kate were spending the weekend with her parents in buckle berry, when she took ill. The prince drove his wife 50 miles to this london hospital, where she was placed on an i.V. Drip. Rumors started swirling last fall, when kate passed on an offering of peanut paste. But speculation went into superdrive last week when the couple was visiting cambridge. A smiling prince accepted a baby onesie, printed with the words daddy's little co-pilot. Kate appeared in high spirits when visiting her old prep school. Even taking to the field hockey field in her boots. The couple who got engaged in 2010, have always been open about their desire to start a family. I think we'll take it one step at a time. We'll get over the marriage thing first. And then, look at the kids. But obviously, we want a family. So, we'll have to start thinking about that. Reporter: Almost immediately after they wed, the world was on royal baby watch. Something the prince spoke to katie couric about in may. It is quite strange reading about it. But I try not to let it bother me. I'm very keen on having a family. And katherine and I would like to have a family in the future. Is there anything you want to tell me about that? You won't get anything out of me. Tight-lipped. Well-wishes have been pouring in and burning up the tilterverse. Maria shriver piped in, saying wonderful news. I had that with my last child. Not fun at all. And lama hasan is here in london, outside the hospital where kate is being treated with more on that. Llama? Reporter: Good morning, lara. Just moments ago, we saw prince william dash into the hospital behind me, to visit his wife, kate, who is being treated by the queen's former doctor. The palace confirms to abc news, that kate will need to remain here for several days. And then, will require a period of rest. Now, kate did have at least three events scheduled this week. She won't be able to attend any of those. And her diary has been cleared for the immediate future.

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